Drover's Cattle Network
The current spring calving season is still in full swing but it’s never too early to make plans for next year’s calf crop – from deciding when to turn out bulls to selecting semen to use for
artificial insemination service and more. For commercial producers who already use AI service in their herds, according to researchers at the University of Idaho, it’s also time to consider whether it makes sense – from a management and economic standpoint – to consider using gender-sorted semen. The commercial availability of gender-sorted semen from beef bulls is relatively new to the scene and the number and genetic diversity of beef bulls with gender-sorted semen is limited compared to that of AI beef bulls with conventional semen. As with any new technology, there are some limitations producers should consider when weighing the pros and potential cons of utilizing gender-sorted semen. First, pregnancy rates are decreased between 10 and 20 percent compared to conventional semen. While fixed-time AI systems (FTAI) work with gender-sorted semen, cows or heifers that are inseminated based on estrus or exhibit of estrus before FTAI have a greater pregnancy rate to gender-sorted semen the researchers say. According to the researchers from Idaho, there is considerable variation in pregnancy rates from bull-to-bull with gender-sorted semen, which could be due to low number of inseminations per bull.
There are multiple potential benefits that could come from utilizing gender-sorted semen in commercial herds, ranging from enhancing genetic progress and shifting gender ratios for marketing purposes.
The use of gender-sorted semen provides commercial producers the opportunity to dedicate a small number of “elite” cows to produce replacement heifers while breeding the remainder of the herd to terminal sires. Over the past five years, the research station at the University of Idaho has used X-sorted semen on 20 percent of its cows to produce Angus-Herford crossbred heifers. The elite cows are identified based on performance records, visual appraisal and, in the near future, custom EPDs. Cows that achieved pregnancy from the gender-sorted semen consistently produced 90 to 92 percent heifer calves. This strategy allowed them to use X-sorted semen to need fewer cows to produce replacement females.
Another potential use on a commercial operation is to use X-sorted semen on all replacement heifers, allowing mature cows to be bred to terminal type sires. According to the researchers from the University of Idaho, genetically, the use of X-sorted semen in replacement heifers could decrease the generation internal, potentially enhance genetic progress and reduce dystocia in heifers.
While more information is needed and it is a high-risk application of gender-sorted semen, the technology could be used to shift gender ratios to enhance marketing potential. Steers weigh more at weaning and are worth more per pound than their heifer counterparts, according to USDA. Thus, using Y-sorted semen to increase the ratio of steers to heifers could increase return per cow. In smaller operations, those with less than 200 cows, this application may allow a producer to offer single-gender trailer loads. At the University of Idaho, while they achieved a 65:35 ratio of steers to heifers, pregnancy rates were just 38 percent. Further, they are still gathering information related to the impact of the repeated whole herd use of gender-sorted semen on cow retention.
While producers should consider these management strategies, economics is an important factor to also consider. Estimation of the economic cost or benefit is variable and dependent on factors ranging from other production costs, current AI use, pregnancy rates, long-term herd impacts, production environment and potential marketing opportunities. Each commercial operation is different, so producers are encouraged to conduct their own cost/benefit analyses and utilize potential benefit calculators available by semen service providers.
This paper was presented at the 2013 Range Beef Cow Symposium
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